The Human Factor by Joshua Dalzelle (ePUB, MOBI)

Captain Jason Burke is a man apart, and not just because he’s the only of his kind for thousands of lightyears in any direction. The changes to his body and to his genetic code have made him faster, stronger, more able to survive in his dangerous occupation … but they’ve also ensured that he’ll never truly fit in with others of his species. He always assumed he would live and die with his crew and never lay eyes on another human again, he was wrong. The mercenary captain learns through back channel information that Earth may be in danger and, worse, that he may have been a contributing factor. He now faces the choice of ignoring the problem and allowing his own species to fight their own battles, or returning to help and risk making the situation worse. Can he just sit idly by while his species faces such a dire threat?